Kobra jalalipour parizi - M.Sc.student of plant biotechnology, Shahid Bahonar University, kerman, Iran
Sara rahpeyma - Assistant professor of Department of plant biotechnology, Shahid Bahonar University, kerman, Iran
shahram pourseyedi - Associate professor of Department of plant biotechnology, Shahid Bahonar University, kerman, Iran

The Corylus avellana. L, belongs to Betulaceae family, consists of 25 species which merely 9 species are eco-nomically important for breeding programs. Different parts of the plant contain influential types of medicinal metabolites (e.g. paclitaxel is known as a crucial anticancer and antimicrobial). Hairy root culture, also called transformed culture, is an efficient biotechnological process to produce valuable secondary metabolites. It should be emphasized that hairy root has high growth rate in comparison with cultured plant cells. Theoretically speak-ing, several conditions including medium composition and type of explants drastically affect the growth rate of hairy roots. Therefore, the main objective of this study is to determine the medium impact on hairy root growth rate and its establishment. In our experimentWPMhairyWPMrootexplantsWPM of hazelnutMS plant, inoculated with Agrobacterium rhizogenes, left on four different medium , , and and the root length along with lateral root branches were calculated. The results indicated that WPM significantly result in the highest root length and also producing lateral root branches

Corylus avellana, Agrobacterium rhizogenes, hairy root, medium